Open hole staged fracturing well completion pipe string provided with controllable valve and hydraulic control switching pipe string

Abstract

The invention discloses an open hole staged fracturing well completion pipe string provided with a controllable valve and a hydraulic control switching pipe string, which are suitable for well completion processes of horizontal wells and straight wells. The hydraulic control switching pipe string is tripped to open and close the open hole staged fracturing well completion pipe string provided with the controllable valve, so that multilayer-section fracturing well completion construction is realized, and development requirements of low-permeability oil reservoirs and unconventional oil and gas resources are met. The pipe string is sequentially connected with a drill stem running tool, a top suspension packer, a hydraulic control switching retention cylinder, a switchable control valve, an open hole fracturing packer connected with the control valve, a shaft isolating valve and a bottom circulating valve from top to bottom by using a bushing. The hydraulic control switching pipe string comprises a hydraulic control switching tool and a continuous oil pipe; and a set of hydraulic control switching tool is connected to the bottom of the continuous oil pipe. The switchable control valve has the internal drift diameter of the same size; sand fracturing well completion can be performed on a stratum by using the bushing; and thus, requirements of large-displacement and large-scale fracturing reconstruction are met, the crack length, the crack number and the flow guide capacity are increased, and the production capacity and the recovery ratio are effectively increased.

Description

technical field [0001] The invention relates to a well completion device in the petroleum industry, especially an open-hole staged fracturing completion string and a hydraulic control switch string with controllable valves, which are suitable for the completion process of horizontal wells and vertical wells. Open-hole segmental fracturing completion strings with controllable valves are installed on the switch strings to realize multi-stage fracturing completions and meet the development needs of low-permeability reservoirs and unconventional oil and gas resources. Background technique [0002] At present, the use of horizontal well staged fracturing technology to improve the development and application scale of unconventional resources such as low permeability reservoirs and shale oil and gas is gradually increasing. However, the currently commonly used horizontal well open hole packer staged completion technology, such as: the application number 200920248979.9 of the horizo...

AI Technical Summary

Problems solved by technology

However, the currently commonly used horizontal well open hole packer staged completion technology, such as: the application number 200920248979.9 of the horizontal well completion and fracturing integrated pipe string, the sliding sleeve staged fracturing technology is opened step by step by throwing balls, in order to allow input The inner diameter of the ball seat at the bottom must be smaller than the inner diameter of the ball seat at the upper level. Affected by the hierarchical arrangement of ball seat sizes, the number of stages and the scale of fracturing are different. It is greatly restricted, which affects the transformation effect; and the sliding sleeve is a ball-pitching sliding sleeve, the sliding sleeve is opened after the ball is thrown in, and it cannot be closed in later production

If selective production or repeated fracturing is to be carried out in the later stage, the sliding sleeve needs to be closed, and the integrated pipe string will not be used as a whole

The tubing fracturing string can only be rerun into the tubing string for small-scale in-pipe segmental fracturing, so it cannot meet the use requirements in the follow-up construction after the completion of the well

At the same time, the structure of the utility model integrated well completion and fracturing string is relatively complex, and it is prone to operational failures.

In the development of low-permeability reservoirs and unconventional oil and gas resources, for vertical wells with multi-stage fracturing, especially horizontal wells with complex string structures and high technical requirements, there is no casing fracturing completion method that can solve the above problems. Restricting the development of low permeability reservoirs and unconventional oil and gas resources

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